sex, shrimp, cycling and pet store holocaust

Hi, i'm new to this whole axolotl thing, and spent a long while reading through this forum before i invested in my new buddy Aristotle. He's great and has been keeping me company, and is in much better health than when I first purchased him. The store had not only bad gravel, but also badly diseased axolotls and in fact a dead one floating around in the tank. Very sad. I am considering notifying the RSPCA.

Anyway, on a lighter note, Aristotle is doing well, and I just had a few questions about him.

Firstly, can anyone work out his age, sex and colour from the images? The store said he was 16 months old, but i'm fairly certain they had no idea. He's about 4-5 inches long. Is he white or albino, is there a difference? As for sex, i don't see much of a lump, so hopefully he's a male?

I am also interested in purchasing a little friend whom I shall name Cornelius to hang out with him. I have heard horror stories about feeder fish, so i assume that's not a great idea. But what about putting a shrimp (Caridina multidentata) in with him? He can chase it around and stuff, anyone have any thoughts on shrimp?

The other issue I have is cycling. The testing kits are way out of my budget at this stage. I managed to get my whole setup, axolotl included for under $100 (if anyone in melbourne wants some tips on where to get aquarium stuff cheap, i can point you in the right direction). I have no idea what the ammonia and nitrite levels are, and thus have been doing water changes and cleaning operations on a daily basis. Still the water is somewhat murky, but Aristotle appears to be doing fine. If he is suffering from too much ammonia/nitrite will he just suddenly keel over and die, or will there be warning signs, infections etc.?

Otherwise, all is well for Aristotle. I've taught him to catch axolotl pellets, and he's very interactive, animated and organic. Some hot days are approaching so I have frozen some water bottles for him in advance.

If anyone can offer me any advice it would be greatly appreciated. Cheers;
Aristotle and Tom.

4-5 inches long would be way too young/small to tell what gender he is. Keeping him with a friend at this stage might not be a great idea either - they'll probably bite each other, wait until they get over 6 inches. He's probably younger than 16 months by quite a bit. A lump actually would mean that he was male, but he's too small for that anyway. Your shrimp Idea sounds like it wouldn't harm your axolotl, but it would most likely end either with the shrimp being eaten, injured, or stressed to death.

I know of many hobbyists who do not have test kits. Most LFS's will do a water test for you on a periodic basis in exchange for buying your supplies there. Waste products in the water can increase steadily without any outward symptoms till they reach critical levels and then the problems happen fast. Unless you are prepared with spare tanks, filters etc you will be scrambling to deal with it. It is far better to get the water tested and make small adjustments to your husbandry technique as needed.